Conveyer for stokers



Dec. 16, 1930. F. C. PICKARD GQNVEYEB FOR STOKERS Filed Dec.

ATTORNEY Patented Dec. 16, 1930 UNITED STATES.

PATENT OFFICE FRANK c. PICKARD, 0E ERIE, PENNSYLVANIA, AssIGNoR To THE STANDARD STOKER COMPANY, INCORPORATED, A CORPORATION 013 DELAWARE CONVEYER FOR STOKERS Application filed December 18, 1928 Serial No. 326,869.-

My invention relates to the fuel conveying system of a stoker and more especially to a the conveyer element or screw adapted to. ro-' tate therein.

In the stoker system for which my invention is more particularly designed, the forwardly extending portion of the conduit system leading from the sourceof fuel supply to the firebox of the boiler, has at its end portion an angularly disposed member or elbow which is adapted to turn or direct the fuel upward as it is conveyedor fed forward by the conveyer screw. The forward end of this screw terminates at the turn or' elbow proper and as thefuel is turned or forced upward through the elbow and the riser connected thereto, the re-action' tends to lift or raise the forward end portion of the screw overcoming gravity which tends to maintain the screw at the bottom of the conduit. Advantage has been taken of this fact to provide at the upper side or roof of the straight part of the elbow a reinforced portion curved to conform with the screw and providing an extended bearing surface for the outer edge or face of the screw thread as it rotates. This of point or line contact, reduces or restricts the wear and prolongs the life of the elbow.

It will be understood that when the screw is stopped, it will fall away from the bearing surface above it. The invention has the further advantage of being adapted to existing constructions without material change therein. In the example shown, the invention has been applied to an elbow having a fiat roof and in such constructions it is carried out by slightly increasing the thickness or reinforcing the roof for a sufficient distance width-wise to provide for the curved bearing surface at the under side, this distance varying with the different sizes of conveyers, but in the present form shown it is some 5 to 6 inches. The thickness'or reinforcing is toflbe ended before it reaches a point where it will interfere with the recesses provided in type of conduit and which have been found highly advantageous in minimizing the tendency of the fuel to rotate without being advanced or fed. I

To the above and other ends which will hereinafter -appear, the invention consists in the features of construction, combinations of devices and arrangements of parts subsequently set forth and particularly pointed out in the appended claims.

The invention will be described more in detail in connection with the accompanying drawing, wherein a Fig. 1 is a fragmentary elevation of the stoker embodying my invention, parts being sectioned and brokenaway for the sake of clearness;

Fig. 2 is a vertical sectional view taken on a plane indicated by the section line 2-2 in Fig. 1;

Fig. 3 is a perspective view of the conduit elbow or element shown detached;

Fig. 4 is a fragmentary side elevation of a modified construction; and

Fig. 5 is a vertical sectional view taken on a plane indicated by the section line 55 in Fig. 4. 4

The stoker embodying the present form t my invention is of the type employed with locomotive engines. The conduit system of the stoker' comprises a conduit tube or element 1O connected at its rear to another con-- duit element (not shown but which, as is well understood, is comprised "in a system leading from the source of fuel supplyon the tender of the locomotive. tube 10 is an angular conduit element 11 usually termed an elbow and which is flanged Forward ofthe at its rear'end to enable it to'be bolted or otherwise secured to the element 10. The elbow 11 comprises a horizontal portion 12 and an upwardly curving portion 13 which at its top is suitably connected'to 5i riser or mouth element 14. The elbow 11 passes under the rear leg 15 of the locomotive boiler and the riser extends upward-within the firebox or combustion-chamber 16 of the boiler, being housed or protected by a grating 17. Means for distributing the fuel as it is forced upward out of the riser comprise adistributor head 18 which is connected as by-pi ping 19.

- with a steam or other fluid-supply system. The elbow ll may be .formedof a single Y casting and may have lateral foot portions 11a adapted'to a support 20 mounted on the framew'orkof the locomotive indicated gene'rally at 21. V

. ',Disposed.wit hin the conduit system is a conveyer system, the forward end portion of which comprises a conveyer screw section 22 terminating at or in the vicinity of the curved portionfi113 of the elbow." As is well understood, t e conveyer or screw isturnedor 1'o-' 'tated by mechanical means, thus advancing or feeding the fuel forward from the source of supply through the conduit system. As the fuel reaches the curved portion 13 of the elbow 11 it is turned or directed upward and forced through the riser 14 and out of its top.

' 2o Gravity of course tends to maintain the conveyerlscrew 22 down in contact with the bottom of the conduit; but the reaction at. the elbowtends to lift the forward portion of 2 the screw 22, the result being in the existing 25 devices of a cutting orwearing away of the roof portion.

Advantage has beentaken of this lifting action of the screw to provide for a novel bearing in the roof or top of the horizontal portion 12 of the elbow member. As .will-be 12a are generally vertical or parallel and the roof 12b is generally flat or horizontal. In carrying out the invention the roof is preferably reinforced or thickened as indicated at 120- and the under or inner face of this-reinforced portion is curved or shaped as indicated at 1% in conformity withthe perimeter of the conveyer screw and of the bot tom of the elbow. In other words, the curvature at 12a? is substantially concentric with the screw 4 as it turns about its center-of rotation 22a.

This construction provides instead of a restrictedor limited point ofbearing contact for. the screw an extended bearing face which may affordsomething like five inches inwidth of surface contact, when used with a screw of approximately 9" in diameter. g The length of the thickened portion, as'will be observed from Fig. 1, provides forengagement with one turn only ofthe screw, thus avoidingunnecessary friction which would result ifthe bearing were extended in length. 'When at rest the forward end of theconveyer" screw may contact with the bottom of 0 theconduit as shown in Fig. 1 but in operaa. it rot'ates.

Wise alter the shape and design of the parts g as it automatically during operation,

The improved construction does not other to minimize useless churning and posed portion sothatre cesses23 are left within the conduit romote theadvance of the fuel therethroug under the rotating action of the screw conveyer.

A modification of the invention is illus- 'trated in Figs. 4 and 5 which show a-form of elbow 11b having'a detachable roof portion 24 secured in place b bolts or screws 25. The roof portion 24 is t ickened or reinforced as in the prior construction so as to rovide an extended bearing surface24a for t e conve yer screw 22 as it lifts or rises during operationotherwise the construction is substantially the same as that shownin Figs. 1 and 3. It possesses the advantage, however, of enabling the roof sectionto be discarded when worn out without necessitating replacement of the conduit as a whole; and it s to ,be understood that its use is not restricted to locomotive stokers or to mechanical stokers of any specific construction.

It will be apparent the bearing'surface 1211 or 24a takes place 'that the surface contact increases, thereby further reducing the wearing or cutting action of the screw and increases the life of the elbow casting.

Various other changes may be made without departing, from t e spirlt and scope ofthe invention.

I claim:

- 1. A'conduit elbow for astoker having up-' right sides and a roof portlon, the mner face of its roofportion' being provided with a curved bearing surface terminating short of said upright sides.

2. A conduit elbow for a stoker havin upright sides and a flat roof port-ion, sai flat surface curved concentrically with the screw said upright sides.

that as the wear of 3. An angular'conduit elbow for a stoker,

. said element comprising a horizontally'disand an upwardly curved or elbow portion,

the roofof thehorizontalportion having a depending segment pro-- viding recesses orpockets between the s1des of said depending segment and the inner wall x of said horizontally disposed portion, the bottom surface of said depending segment being curved toprovide a bearing surface for. a conveyer screw.

. 4. In a stoker, the combination of a conduit system comprising a; horizontally disposed portion and an upwardly curved portion, a I

conveyer screw disposed withinthe horizontallygdisposed portion and terminating at the upwardly curved portionflihe forward upright sides and a roof formed with'f'a curved bearing surface for the threadjof. the-{screw part of the horizontally disposedportion just I V a I and providing opposite sldes of the curved bearing surface said curved bearing surface terminating short of said upright sides.

5. In a stoker, aconduit member adapted to receive a conveyer screw, said member considered in cross section havinga curved bottom and a reinforced-flat top or roof curved at its under side in conformity with the screw and providing a bearing surface for said screw, the sides of the member being upright fuel recesses or pockets at of the roof.

6. In a stoker, aconduit member adapted to receive a conveyer, screw, said member having an arcuate shaped bottom, a substantially horizontal top or roof a portion of which at its under side is curved concentrically with said conveyer screw and providing a bearing surface for said screw, the side walls of the member extending upwardly from its arcuate bottom to its top or roof, said side walls and roof providing at their intersectionrecesses or pockets at opposite sides of the curved bearing surface of the roof.

In testimony whereof I affix'my signature.

F. c. PICKARD. 

